1. Field of the Invention
An aspect of the present invention relates to a plasma display device and a driving method thereof, and more particularly, to a plasma display device and a driving method thereof which can prevent address discharging from low discharging. The driving method of the plasma display device includes a plasma display panel having first to third electrodes, a frame divided into a plurality of sub-fields, and each sub-field divided into a reset period, an address period, and a sustain period, the method comprising: among the first electrodes classified in a plurality of groups including a first group and a second group for the address period, sequentially supplying the first group with a scan pulse, supplying a sub scan pulse to the second group, and sequentially supplying the second group with the scan pulse.
2. Description of the Related Art
The plasma display panel forms an image by using a visible ray that is emitted from a phosphorous material, which is excited by ultraviolet rays generated by plasma obtained by a gaseous discharge. The plasma display panel is sealed and a gas is injected into a space formed between an upper substrate and a lower substrate opposite to each other. A plurality of first and second electrodes alternatively arranged are formed on one side of the display panel between the upper substrate and the lower substrate. A third electrode arranged along a direction that crosses the first and second electrodes is formed on the other side. A discharging cell is formed on the area where the plurality of electrodes intersect, in order to form a unit pixel of the plasma display panel.
The driving method of the plasma display device including the plasma display panel includes an Address and Display period Separated (ADS) driving method. The ADS driving method is a method where a frame is divided into a plurality of subfields, each subfield having a weight value, and each subfield is time-divided to represent gray scale for image display. Each subfield is formed with a reset period, an address period, and a sustain period.
The reset period is a period for rearranging wall charges which are formed in a previous period. The address period is a period for generating a wall discharge needed to sustain discharging in an on-discharging cell. The sustain period is a period for displaying an image on the plasma display panel by using wall charges generated for the address period.
Generally, in the address period, a scan pulse is sequentially supplied to the first electrodes while a bias pulse is supplied to the second electrode. As a result, the on-discharging cell performs the address discharging and thus a wall charge needed for a sustain period is generated. However, this driving method has a disadvantage in that as the number of the first electrodes needed to form a high resolution plasma display panel increases, the closer the electrodes are to each other and the longer the latency time before supplying the scan pulse. Therefore, this can result in scatter and loss of a wall charge rearranged by reset discharging. By losing this wall charge, low discharging occurs in address discharging.